//
// Event_POSIX.cpp
//
// $Id: //PIL/1.4/Foundation/src/Event_POSIX.cpp#3 $
//
// Library: Foundation
// Package: Threading
// Module:  Event
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier:	BSL-1.0
//


#include "Event_POSIX.h"
#if defined(PIL_VXWORKS)
#include <timers.h>
#include <cstring>
#else
#include <sys/time.h>
#endif


namespace pi {


EventImpl::EventImpl(bool autoReset): _auto(autoReset), _state(false)
{
#if defined(PIL_VXWORKS)
    // This workaround is for VxWorks 5.x where
    // pthread_mutex_init() won't properly initialize the mutex
    // resulting in a subsequent freeze in pthread_mutex_destroy()
    // if the mutex has never been used.
    std::memset(&_mutex, 0, sizeof(_mutex));
#endif
    if (pthread_mutex_init(&_mutex, NULL))
        throw SystemException("cannot create event (mutex)");
    if (pthread_cond_init(&_cond, NULL))
        throw SystemException("cannot create event (condition)");
}


EventImpl::~EventImpl()
{
    pthread_cond_destroy(&_cond);
    pthread_mutex_destroy(&_mutex);
}


void EventImpl::waitImpl()
{
    if (pthread_mutex_lock(&_mutex))
        throw SystemException("wait for event failed (lock)");
    while (!_state)
    {
        if (pthread_cond_wait(&_cond, &_mutex))
        {
            pthread_mutex_unlock(&_mutex);
            throw SystemException("wait for event failed");
        }
    }
    if (_auto)
        _state = false;
    pthread_mutex_unlock(&_mutex);
}


bool EventImpl::waitImpl(long milliseconds)
{
    int rc = 0;
    struct timespec abstime;

#if defined(__VMS)
    struct timespec delta;
    delta.tv_sec  = milliseconds / 1000;
    delta.tv_nsec = (milliseconds % 1000)*1000000;
    pthread_get_expiration_np(&delta, &abstime);
#elif defined(PIL_VXWORKS)
    clock_gettime(CLOCK_REALTIME, &abstime);
    abstime.tv_sec  += milliseconds / 1000;
    abstime.tv_nsec += (milliseconds % 1000)*1000000;
    if (abstime.tv_nsec >= 1000000000)
    {
        abstime.tv_nsec -= 1000000000;
        abstime.tv_sec++;
    }
#else
    struct timeval tv;
    gettimeofday(&tv, NULL);
    abstime.tv_sec  = tv.tv_sec + milliseconds / 1000;
    abstime.tv_nsec = tv.tv_usec*1000 + (milliseconds % 1000)*1000000;
    if (abstime.tv_nsec >= 1000000000)
    {
        abstime.tv_nsec -= 1000000000;
        abstime.tv_sec++;
    }
#endif

    if (pthread_mutex_lock(&_mutex) != 0)
        throw SystemException("wait for event failed (lock)");
    while (!_state)
    {
        if ((rc = pthread_cond_timedwait(&_cond, &_mutex, &abstime)))
        {
            if (rc == ETIMEDOUT) break;
            pthread_mutex_unlock(&_mutex);
            throw SystemException("cannot wait for event");
        }
    }
    if (rc == 0 && _auto) _state = false;
    pthread_mutex_unlock(&_mutex);
    return rc == 0;
}


} // namespace PIL
